1. During a storm, you heard thunder shortly after you saw a flash of lightning. Explain why there is a difference in time between seeing the lightning and hearing the thunder.

Different speeds of sound and light

2. The moon makes no light but appears to shine at night.
Explain why.

Sun shines on the moon
then light is reflected to earth

3. Which statement explains why daylight and darkness occur on Earth?

a. The Earth rotates on its axis.
b. The Sun rotates on its axis.
c. The Earth's axis is tilted.
d. The Earth revolves around the Sun.

4. Draw an arrow on the river to show the way that the water flows.

year 8 only
5. Sometimes mountains can still have snow on their tops when the snow on the lower parts of the mountain has melted. What makes this happen?

Colder at high altitudes

6. Whenever scientists carefully measure any quantity many times, they expect that

a. all of the measurements will be exactly the same.
b. almost all of the measurements will be exactly the same.
c. two or three of the measurements will be exactly the same.
d. most of the measurements will be close but not exactly the same.